Bug 956230: improve instrumentation of bugzilla's internals

1 files changed, 101 insertions, 0 deletions

diff --git a/Bugzilla/Metrics/Reporter.pm b/Bugzilla/Metrics/Reporter.pm
new file mode 100644
index 000000000..42d2c3abc
--- /dev/null
+++ b/Bugzilla/Metrics/Reporter.pm
@@ -0,0 +1,101 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+#
+# This Source Code Form is "Incompatible With Secondary Licenses", as
+# defined by the Mozilla Public License, v. 2.0.
+
+package Bugzilla::Metrics::Reporter;
+
+use strict;
+use warnings;
+
+use Bugzilla::Constants;
+use File::Slurp;
+use File::Temp;
+use JSON;
+
+# most reporters should detach from the httpd process.
+# reporters which do not detach will block completion of the http response.
+use constant DETACH => 1;
+
+# class method to start the delivery script in the background
+sub background {
+    my ($class, $collector) = @_;
+
+    # we need to remove parent links to avoid looped structures, which
+    # encode_json chokes on
+    _walk_timers($collector->{root}, sub { delete $_[0]->{parent} });
+
+    # serialisation
+    my $json = encode_json({ env => $collector->{env}, times => $collector->{root} });
+
+    # write to temp filename
+    my $fh = File::Temp->new( UNLINK => 0 );
+    if (!$fh) {
+        warn "Failed to create temp file: $!\n";
+        return;
+    }
+    binmode($fh, ':utf8');
+    print $fh $json;
+    close($fh) or die "$fh : $!";
+    my $filename = $fh->filename;
+
+    # spawn delivery worker
+    my $command = bz_locations()->{'cgi_path'} . "/metrics.pl '$class' '$filename' &";
+    system($command);
+}
+
+# run the reporter immediately
+sub foreground {
+    my ($class, $collector) = @_;
+    my $reporter = $class->new({ hashref => { env => $collector->{env}, times => $collector->{root} } });
+    $reporter->report();
+}
+
+sub new {
+    my ($invocant, $args) = @_;
+    my $class = ref($invocant) || $invocant;
+
+    # load from either a json_filename or hashref
+    my $self;
+    if ($args->{json_filename}) {
+        $self = decode_json(read_file($args->{json_filename}, binmode => ':utf8'));
+        unlink($args->{json_filename});
+    }
+    else {
+        $self = $args->{hashref};
+    }
+    bless($self, $class);
+
+    # remove redundant data
+    $self->walk_timers(sub {
+        my ($timer) = @_;
+        $timer->{start_time} = delete $timer->{first_time};
+        delete $timer->{children}
+            if exists $timer->{children} && !scalar(@{ $timer->{children} });
+    });
+
+    return $self;
+}
+
+sub walk_timers {
+    my ($self, $callback) = @_;
+    _walk_timers($self->{times}, $callback, undef);
+}
+
+sub _walk_timers {
+    my ($timer, $callback, $parent) = @_;
+    $callback->($timer, $parent);
+    if (exists $timer->{children}) {
+        foreach my $child (@{ $timer->{children} }) {
+            _walk_timers($child, $callback, $timer);
+        }
+    }
+}
+
+sub report {
+    die "abstract method call";
+}
+
+1;